Enclosed direct lighting luminaire



NOV. W. BEALS v 4:.\':' "SD DIRECT LIGHTING LUMINAIRE y Filed om. 18, 1939 2 sheets-sheen i 1NVENTOR. G/uso/v h/ 9F/Ms l 47 Y MMM ATTORNEY.

Nov. 11, 1941.

ATTORNEY.

Patented Nov. l1, 1941v ENCLOSED DIRECTV LIGHTING LUMINAIRE Gillson W. Beals, Meriden, Conn., assignor to The Miller Company, Meriden, Conn., a corporation of Connecticut Application October 18, 1939,?1flgferial No. 299,941 v (Cl. 24o-78) 9 Claims.

This invention relates to enclosed direct lighting luminaires, and is more particularly directed toward luminaires designed to employ fluorescent light sources and to be used in dust laden atmosphere. u

The present invention contemplates luminaires particularly suitable for use in locations where explosive powder is being manufactured and handled. The luminaires are designed so as to present practically no exposed horizontal surfaces on which the powder or other dust could accumulate, and are .arranged to have large extensive radiating surfaces so that the fixture has an inconsequential temperature rise after long use.

A further object of the invention is to provide the fixture with a door which is effectively sealed against the introduction of dust.

, A further object of the invention is to'arrange' ythe interior of the xture so that when the door is opened to give access to the lamps there is a minimum possibility of dust filtering into the interior of the xture.

A further object of the invention is to provide a fixture designed for the use of long light sources, such as iiuorescent lamps, with a door opening long enough to accommodate the lamps and reiiectors. 4

The accompanying drawings show, for purposes of illustrating the present invention, one of the many embodiments in which the invention may take form, it being understood that the drawings are illustrative of the invention rather than limiting the same.

I In these drawings:

Figure 1 is a perspective view of an enclosed direct lighting luminaire;

Figure 2 is a transverse `section through the same taken onthe line 2-2 of Figure 3;

Figure 3 is a longitudinal sectional view taken on the line 33 of Figzre 2 with parts in elevation, and parts at the left hand section on the line 3a-3a of Figure 2;

Figure 4 is a fragmentary sectional view on the line 4-4 of Figure 2;

Figure 5 is a fragmentary sectional view on the line 5-5 of Figure 3; and

Figure 6 is a top plan view of the iixture with parts broken away to show interior construction.

As shown in Figure l the fixture is supported by two pipes or 'conduits I II, III which thread into junction boxes II, II. These junction boxes are provided with removable plates I2 and gaskets I2' adapted to give access to the wiring.

The junction boxes are secured to a sheet metal cover or housing I3 by welding bolts indicated at 55 I4. It has straight sloping sides and a rounded apex portion, as will be clear from Figure 2, so that a. minimum horizontal area is presented for the accumulation of dust. The lower edges I5, I5 of the cover member I3 are secured to longitudinally extending frame members I6, I6 by screws I1, a gasket I6' being interposed to seal the joint. The ends of the cover member I3 are secured to end plates I 3 by screws indicated at I9, these screws passing through gaskets I9 and into vflanges 20.

Inner end members 2I are secured to the end plates I8 by screws indicated at 22. The end plates 2l have sloping side edges 23 which overlie the flanges 20 on the end plates I8 and have up; wardly and rearwardly sloping elements indicated at 24 and 25 which extend out to the inner face of the adjacent end plate I8.

The end members 2I are' secured to the ends of the side frame members I6 by screws 26, as indicated in Figure 4. The inner end members 2| support pairs of iiuorescent lamp-holders 21, 21 adaptedto receive fluorescent lamps 28, 28. The end members 2I are also provided with flanges 29 of the proper shape to t the ends of sheet metal refiectors 30. The reflectors are secured to the end members 2I by screws indicated at 3l. Closure plates 32 are secured to the side frame members I6 by screws 33 and bear on the outer edges of the reflectors 30, 30. A longitudinally extending closure strip 34 is secured at its ends to the end members 2I by screws indicated at 34.'. The strip 34 is of channel shaped cross section .and is secured to the adjacent edges of the reflectors 30, 30 by means of screws 35 and short straps 38, the latter being adapted to bear fon the beads at the edges of the reflectors.

The side frame member IE at the right of Figure 2 supports one leaf 31 of a hinge 38, while the other leaf 39 supports a window 40. This win dow is made up of a large rectangular panel of glass or other light transmitting material, as indicated at 4I, and has a frame 42 of channel shaped cross section as indicated in the drawings. The edges of the glass are received in gaskets 4I This frame is made of two parts 42a and 42h, as

indicated more clearly in Figure 5. One of these parts is welded to a lug 43, while the other part is welded to a strap 44 arranged to overlie the lug 43. The strap 44 is provided with a slotl 45 to receive a screw 46 which may be threaded into a tapped hole in the lug 43. This arrangement of securing the ends of the parts 42a and 42b together is duplicated at the other end of the fixture.

The edge ofr the Window oppositethe hinge is secured to the opposite frame member by latches v 41. It will be noted from the drawings that the end members'2'l and side members I6 are cut back to receive the window frame so that the window frame can be brought against gaskets indicated at 48 to make a tight joint. Furthermore, as will be apparent from Figure 3, the window frame is set back from the inner faces of the end members 2| so as not to interfere with the escape of light longitudinally of the xture. This arrangement also makes it possible to avoid projections or other elementswhich would interfere with insertion or removal of lamps. The lamps 28 are connected to fluorescent lamp auxiliary units 49 only one of whichyappears inffthe drawings. These units are supported by cross straps 5U welded to the cover member I3.

Owing to the use of the closure plates 32 and 24 and to the closeness with whi the reectors are fitted to the end plates, there is very little opportunity for dust to enter into the interior of the xture when the door is open.

It is obvious that the invention may be embodied in many forms and constructions within the scope of the claims and I wish it to be understood that the .particular form shown is but one of the many forms. Various modifications and changes being possible, I do not otherwise limit myself inV any way with respect thereto.

What is claimed is:

1. ,A totally enclosed direct lighting luminaire for use in dust 'laden atmophere, comprising a horizontal frame-having two sides and two end members to form a rectangular opening, a light transmitting dust tight .closure fitted into the opening, the end members of the frame extendin'g upwardly and supporting pairs of fluorescent lamp-holders, iluorescent lamps in the holders, inverted trough shaped refiectors secured to the end members and disposed about the lamps to the frame and the ends of the cover being se- I /50 tending from one end member to the other, a

rectangular window having a frame hinged to e cured to the outer end plates 2. A luminaire such as claimed in claim 1,/ wherein the end members of the frame have inwardly extending flanges conforming to the contour of the reflector walls.

3. A luminaire such as claimed in claim 1, having strips extending inwardly from the sides of the frame to engage the outer walls of the refiectors.

4. A luminaire such as claimed in claim 1, having strips extending inwardly from the side members 'of the frame to engage the outer walls of the reflectors, a filler strip secured 'to the adjacent walls of the reflectors, and wherein the end members ofthe frame have inwardly extending flanges conforming to the contour of the reflector walls. A f

5. A luminaire such as claimed in claim 1, hav- 5 ing transyerse reinforcing straps carried by the cover above the reflectors and fluorescent lamp elongated, inverted. trough like housing of V- shapedl cross section to provide substantially no horizontal surface for accumulation of dust, vere tical end plates, end members secured to the inn`er face of an end plate and having a-vertical wall spaced from the end plate, iluorescent lampholderssecured to the end inembers, fluorescent lampsin the holders, reflectors about thelamps ,and extending from one end member to the l other, side members securedto the end members and to the lower edges ofthe housing, a rectangular frame removably.A secured in the opening formed by the end and side members, the end members being-recessed so that the end members of the frame are accommodated therein, and a dust tight mgm transwmming pme carried in the frame.

TI. Av direct "dighting iixture forv long light sources, comprising a downwardly opening trough shaped cover, end plates secured to the ends of the cover, longitudinally extending frame members secured to the end plates and to the edges of the cover to form a rectangular opening, a dust tight, light transmitting closure in said lopening, two downwardly opening .reflectors above the closure, means interconnecting the lower outer edges of the reectors with the adjacent lower edges of the cover to prevent passage of dust therebetween, a dust tight closure strip between 'adjacent edges of the reilectors,

40 iiuorescent lamps disposed in the reflectors and iiuorescent lamp auxiliary units carried in the lcover above the reiiectors.

8. In a direct lighting unit, two vertical end members carrying fluorescent lamp-holders arranged in pairs, side members secured to the end members to form a rectangular opening and of a length to space them so that the lamp-hold- A ers maysuppormiorescent lamps of predetermined length, reectors about the lamps and exone side member and occupying the opening, vertical end plates secured outside the end members, and an inverted V-shaped cover secured to the end plates and side members. 9. A lighting unit such as claimed in claim 8, having dust tight strips extending from the side members to the edges of the reiiectors adjacent thereto and a dust tight closure strip interconnecting the edges of the reiiectors adjacent one another.

GDLLSCN W. BEALS. 

